The U.S. Internal Revenue Service is drafting a policy to restrict the use without a warrant of cell-site simulator technology to snoop on the location and other information from mobile phones.
The head of the IRS, John Koskinen, wrote in a letter that the agency was drafting a policy that would mirror an earlier Department of Justice rule, which requires a search warrant supported by probable cause before using the technology, except in exigent or exceptional circumstances.
Cell-site simulators, also referred to as stingrays or ‘IMSI catchers,’ track the location and other information from mobile phones by mimicking cellphone towers. The use of the technology without a warrant by law enforcement has been criticized by civil rights groups.
The Criminal Investigation division of the IRS first deployed the cell-site simulator in 2012, according to Koskinen’s letter to Senator Ron Wyden. Since then the IRS-IC tracked 37 cellular devices in support of 11 federal grand jury investigations. The investigations were led by the U.S. Attorney’s Office, which provided guidance in obtaining necessary authorizations, including court orders and tracking warrants, Koskinen wrote. The IRS also used the device in four other investigations that required the tracking of seven cellular devices.